Institute of Coal Chemistry, Chinese Academy of Sciences,
Keywords: graphene, electrochemistry, energy management
Summary:I’d like to present that graphene flakes have been produced with good properties and potentially used widely through electrochemical approaches. The electrochemically exfoliated graphene-based materials exhibit high performances in thermal management, electrocatalysis, supercapacitor, batteries and biosensor.1-12 Tunable atomic layers, sheet sizes, defects, pores and atomic hybridization of graphene could be electrochemically synthesized (Figure 1). Small graphene microsheets directly produced from natural microcrystalline graphite minerals at large scale exhibit high reversible specific capacity as a battery anode material and also cathode material after modification.2-4 The microsheets are highly dispersible in water or solvent up to 20wt%. Atomic iron/graphene synthesized via electrochemical exfoliation of graphite in iron-based ionic liquid following annealing with melamine show superior electrocatalytic performance on oxygen reduction reaction to Pt/C.5 >30 μm of large literal sheets of 1-2 layer graphene sheets were used to fabricate robust, flexible and free-standing graphene films or carbon fiber/graphene hybrid film with high thermal diffusivity and electromagnetic shielding. It shows a great potential for a lighter and stronger current collect to replace metal current collector for energy storage and high thermal conductivity film after high-temperature treatment. Graphene could significantly reduce activation temperature of carbon resources (such as cellulose, pitch) with energy saving and more safety. The hierarchical porous graphene/carbon-based supercapacitors reach >200 F/g (3.5V) in ionic liquid and high energy density of >60 Wh/kg at high rate 6 Graphene integrating carbon fiber and activated carbon as a robust and multifunctional carbon “concrete” show a potential of integrating automobile body and energy storage.7 graphene nanostructures exhibit high performance on bi-functional electrocatalyst and Zinc-air battery.8.9 Graphene-based Li-S batteries reach >99.5% coulombic efficiency and 2000-cycle stability.10 electorchemical biosensor are also interesting.11,12. Our investigation demonstrated that electrochemical route is very promising for the production and wide application of graphene materials.